Answers to Questions 3 to 5
3a State the Number of Neutrons and protons in the following:
226Ra88 = 88 protons and 138 neutrons
1H1 = 1 proton and 0 neutrons
239Np93 = 93 protons and 146 neutrons
Answers to Questions:
6. Complete the following:
a) 32P15 ---> 0e-1 + ??? = 32S16
b) 234Th90 ---> ??? + 234Pa91 = 0e-1
c) 22Na11 ---> ??? + 0e+1 = 22Ne10
d) 1n0 ----> ??? + 1H1 = 0e-1
e) 1H1 + 0e-1 ---> ??? = 1n0
7. What are the parent nuclei for each of the following daughter nuclei produced by alpha (4He2) decay:
a) 206Tl81 = 210Bi83
b) 210 Thallium (81) = 214Bi83
c) Po-218 or 218Po84 = 222Rn 86
d) Pb-206 or 206Pb82 = 210Po84
8. Write equations for the beta decay of:
a) C-14 or 14C6 ---> 0e-1 + 14N7
b) Na-24 or 24Na11 ---> 0e-1 + 24Mg12
c) P-32 or 32P15 ---> 0e-1 + 32 S 16
9. Write equations for the positron decay of:
a) 22Na or 22Na11 ---> 0e+1 + 22Ne10
b) 18F or 18F9 ----> 0e+1 + 18 O 8
c) 19Ne or 19Ne10 ----> 0e+1 + 19F9
d) 199Pb or 199Pb82 ----> 0e+1 + 199Tl81
Lesson Four:
Half - Life - A half-life is defined as the amount of time required for one-half or 50% of the radioactive atoms to undergo a radioactive decay. This is also known as the "radioactive" or "physical" half-life. Every radioactive element has a specific half-life associated with it. (http://www.iem-inc.com/prhlfr.html )
Key Notes: A is Activity A0 = initial activity (in Bq) A = final activity N = final number of atoms or grams N0 = initial number of atoms or grams n = number of half-life lapsed Equations: InA – InA0 = - λt N = N0e-λt λ = 0.693/t1/2 or A = λN
Lesson Five:
Discuss Radioactive Decay and work through Questions 12 to 18.
Accidents Relating to Nuclear Accidents and Reactor Concerns:
Post1961 Clean-Up
1978 3 Mile Island - United States
On a Wednesday morning, maintenance workers cleaning sludge from a small pipe blocked the flow of water in the main feedwater system of a reactor at Three Mile Island near Harrisburg, Pennsylvania. The sift foreman heard "loud, thunderous noises, like a couple of freight trains," coming. Since the reactor was still producing heat, it heated the blocked cooling water around its core hot enough to create enough pressure to have popped a relief valve. Some 220 gallons of water per minute began flowing out of the reactor vessel. Within five minutes after the main feedwater system failed, the reactor, deprived of all normal and emergency sources of cooling water, and no longer able to use its enormous energy to generate electricity, gradually started to tear itself apart.
The loss of coolant at the reactor continued for some 16 hours. Abort a third of the core melted down. Radioactive water flowed through the stuck relief valve into an auxiliary building, where it pooled on the floor. Radioactive gas was released into the atmosphere. An estimated 140,000 people were evacuated from the area. It took a month to stabilize the malfunctioning unit and safely shut it down. The reactor was a total loss and the cleanup required years of repair and hundreds of millions of dollars.
No one was reported injured and the little radiation that leaked out was quickly dispersed. Although this accident did cost lots of money and time, no one was hurt.
1986 Chernobyl - USSR (Russia)
A far more serious accident occured at Chernobyl, in what was then still the Soviet Union. At the time of the accident, the Chernobyl nuclear power station consisted of four operating 1,000 megawatt power reactors. Without question, the accident at Chernobyl was the result of a fatal combination of ignorance and complacency. "As members of a select scientific panel convened immediately after the... accident," writes Nobel laureate Hans Bethe, "my colleagues and I established that the Chernobyl disaster tells us about the deficiencies of the Soviet political and administrative system rather than about problems with nuclear power."
Although the problem at Chernobyl was relatively complex, it can basically be summarized as a mismanaged electrical engineering experiment which resulted in the reactor exploding. The explosion was chemical, driven by gases and steam generated by the core runaway, not by nuclear reactions. Flames, sparks, and chunks of burning material were flying into the air above the unit. These were red-hot pieces of nuclear fuel and graphite. About 50 tons of nuclear fuel evaporated and were released by the explosion into the atmosphere. In addition, about 70 tons were ejected sideways from the periphery of the core. Some 50 tons of nuclear fuel and 800 tons of reactor graphite remained in the reactor vault, where it formed a pit reminiscent of a volcanic crater as the graphite still in the reactor had turned up completely in a few days after the explosion.
The resulting radioactive release was equivalent to ten Hiroshimas. In fact, since the Hiroshima bomb was air-burst--no part of the fireball touched the ground--the Chernobyl release polluted the countryside much more than ten Hiroshimas would have done. Many people died from the explosion and even more from the effects of the radiation later. Still today, people are dying from the radiation caused by the Chernobyl accident. The estimated total number of deaths will be 16,000.
September 1987 Goiana - South America
Lesson Eight:
Fusion Reactors
H-Bomb - Tsar Bomb - the Biggest Bomb ever exploded:
Lesson Ten:
Applications of Nuclear Technology:
Smoke Detectors
This type of detector is cheaper than the optical detector; however, it is sometimes rejected for environmental reasons and because it is more prone to false alarms than photoelectric smoke detectors. It can detect particles of smoke that are too small to be visible. It includes less than a milligram of radioactive americium 241 (241Am).[2] The radiation passes through an ionization chamber, an air-filled space between two electrodes, and permits a small, constant current between the electrodes. Any smoke that enters the chamber absorbs the alpha particles, which reduces the ionization and interrupts this current, setting off the alarm.
241Am, an alpha emitter, has a half-life of 432.2 years. This means that it does not have to be replaced during the useful life of the detector, and also makes it safer for people at home, as it is less radioactive. Alpha radiation, as opposed to beta and gamma, is used for two additional reasons: Alpha particles have high ionization, so sufficient air particles will be ionized for the current to exist, and they have low penetrative power, meaning they will be stopped by the plastic of the smoke detector and/or the air, reducing the risk of harm to people. (Source: Wikipedia)
Mistakes: Chapter 28
Page 584. The scales on the graph are wrong.
On the y-axis, the 5 x 105 should be half way down next to the dotted line.
On the x-axis, the times should be 0, 15, 30, 45, 60 and the unit should be 'hours' not days.
Question 44. Answer in back of the 1997 edition of the book says Reaction II produces 9.61 x 1012 J/kg. This is wrong - the correct answer is 5.72 x 1014 J/kg) and Reaction II produces more energy per kg than Reaction I
Topics: Chapter 28 Nuclear Physics
Objective and Summary of Key Points - http://seniorphysics.com/ch28obsm2.html
Lesson One:
What is Radiation:
http://en.wikipedia.org/wiki/Radiation
Basic Terms Handout -
Read p576 to 579
Define Ionising and non-ionising radiation
Lesson Two:
What is Transmutation?
Note: a positron is a beta + particle.
Questions:
Geiger Counter Simulation
http://home.clara.net/darvill/nucrad/detect.htm
http://chemistry.binghamton.edu/ilc/labs/radiochem/moviepop/geiger-counter-sim.htm
Answers to Questions 3 to 5
3a State the Number of Neutrons and protons in the following:
226Ra88 = 88 protons and 138 neutrons
1H1 = 1 proton and 0 neutrons
239Np93 = 93 protons and 146 neutrons
4. What element is represented by X in each of the following:
222X88 = http://www.webelements.com/radium/
1X1 = http://www.webelements.com/hydrogen/
247X97 = http://www.webelements.com/berkelium/
82X38 = http://www.webelements.com/strontium/
5. Balance the following equations:
a) 214Bi83 ---> 0e-1 + ??? = 214Po 84
b) 239Np93 ---> 0e+1 + ??? = 239U92
c) 226Ra88 ----> 222Rn86 + ??? = 4He2
d) 45Ca20 ---> 0e-1 + ??? = 45Sc21
e) 58Cu29 ---> 0e+1 + ??? = 58Ni28
f) 234Pu94 ---> 4He2 + ??? = 230U92
Lesson Three:
Recap on Types of Decay
Note Energy given off in the decaying process
Answers to Questions:
6. Complete the following:
a) 32P15 ---> 0e-1 + ??? = 32S16
b) 234Th90 ---> ??? + 234Pa91 = 0e-1
c) 22Na11 ---> ??? + 0e+1 = 22Ne10
d) 1n0 ----> ??? + 1H1 = 0e-1
e) 1H1 + 0e-1 ---> ??? = 1n0
7. What are the parent nuclei for each of the following daughter nuclei produced by alpha (4He2) decay:
a) 206Tl81 = 210Bi83
b) 210 Thallium (81) = 214Bi83
c) Po-218 or 218Po84 = 222Rn 86
d) Pb-206 or 206Pb82 = 210Po84
8. Write equations for the beta decay of:
a) C-14 or 14C6 ---> 0e-1 + 14N7
b) Na-24 or 24Na11 ---> 0e-1 + 24Mg12
c) P-32 or 32P15 ---> 0e-1 + 32 S 16
9. Write equations for the positron decay of:
a) 22Na or 22Na11 ---> 0e+1 + 22Ne10
b) 18F or 18F9 ----> 0e+1 + 18 O 8
c) 19Ne or 19Ne10 ----> 0e+1 + 19F9
d) 199Pb or 199Pb82 ----> 0e+1 + 199Tl81
Lesson Four:
Half - Life - A half-life is defined as the amount of time required for one-half or 50% of the radioactive atoms to undergo a radioactive decay. This is also known as the "radioactive" or "physical" half-life. Every radioactive element has a specific half-life associated with it. (http://www.iem-inc.com/prhlfr.html )
Examples of Half Lives from a variety of elements:
http://lectureonline.cl.msu.edu/%7Emmp/kap30/Nuclear/nuc.htm
Read Text page 585 to 587
The half-life of a radioactive isotope is the time taken for half the radioactive atoms in a sample to decay.
Answers to Questions:
Key Notes:
A is Activity
A0 = initial activity (in Bq)
A = final activity
N = final number of atoms or grams
N0 = initial number of atoms or grams
n = number of half-life lapsed
Equations:
InA – InA0 = - λt
N = N0e-λt
λ = 0.693/t1/2 or A = λN
Lesson Five:
Discuss Radioactive Decay and work through Questions 12 to 18.
Lesson Six:
What is Nuclear Fusion?
Concept simulation of the fusion of deuterium and tritium inside of a tokamak reactor.
http://www.visionlearning.com/library/flash_viewer.php?oid=2747
What is Nuclear Fission?
HAPPY BIRTHDAY ERICA!
http://au.youtube.com/watch?v=DT0ZNPz3t2o
How does a Nuclear Reactor Work?
Learning Objects on Nuclear Reactors - fission control and reacting to emergencies
Revision of Radioactive Decay - http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/radioa7.swf
Lesson Seven:
Hiroshima Bomb - 6th August 1945
Accidents Relating to Nuclear Accidents and Reactor Concerns:
Post1961 Clean-Up
1978 3 Mile Island - United States
On a Wednesday morning, maintenance workers cleaning sludge from a small pipe blocked the flow of water in the main feedwater system of a reactor at Three Mile Island near Harrisburg, Pennsylvania. The sift foreman heard "loud, thunderous noises, like a couple of freight trains," coming. Since the reactor was still producing heat, it heated the blocked cooling water around its core hot enough to create enough pressure to have popped a relief valve. Some 220 gallons of water per minute began flowing out of the reactor vessel. Within five minutes after the main feedwater system failed, the reactor, deprived of all normal and emergency sources of cooling water, and no longer able to use its enormous energy to generate electricity, gradually started to tear itself apart.
The loss of coolant at the reactor continued for some 16 hours. Abort a third of the core melted down. Radioactive water flowed through the stuck relief valve into an auxiliary building, where it pooled on the floor. Radioactive gas was released into the atmosphere. An estimated 140,000 people were evacuated from the area. It took a month to stabilize the malfunctioning unit and safely shut it down. The reactor was a total loss and the cleanup required years of repair and hundreds of millions of dollars.
No one was reported injured and the little radiation that leaked out was quickly dispersed. Although this accident did cost lots of money and time, no one was hurt.
1986 Chernobyl - USSR (Russia)
A far more serious accident occured at Chernobyl, in what was then still the Soviet Union. At the time of the accident, the Chernobyl nuclear power station consisted of four operating 1,000 megawatt power reactors. Without question, the accident at Chernobyl was the result of a fatal combination of ignorance and complacency. "As members of a select scientific panel convened immediately after the... accident," writes Nobel laureate Hans Bethe, "my colleagues and I established that the Chernobyl disaster tells us about the deficiencies of the Soviet political and administrative system rather than about problems with nuclear power."
Although the problem at Chernobyl was relatively complex, it can basically be summarized as a mismanaged electrical engineering experiment which resulted in the reactor exploding. The explosion was chemical, driven by gases and steam generated by the core runaway, not by nuclear reactions. Flames, sparks, and chunks of burning material were flying into the air above the unit. These were red-hot pieces of nuclear fuel and graphite. About 50 tons of nuclear fuel evaporated and were released by the explosion into the atmosphere. In addition, about 70 tons were ejected sideways from the periphery of the core. Some 50 tons of nuclear fuel and 800 tons of reactor graphite remained in the reactor vault, where it formed a pit reminiscent of a volcanic crater as the graphite still in the reactor had turned up completely in a few days after the explosion.
The resulting radioactive release was equivalent to ten Hiroshimas. In fact, since the Hiroshima bomb was air-burst--no part of the fireball touched the ground--the Chernobyl release polluted the countryside much more than ten Hiroshimas would have done. Many people died from the explosion and even more from the effects of the radiation later. Still today, people are dying from the radiation caused by the Chernobyl accident. The estimated total number of deaths will be 16,000.
September 1987 Goiana - South America
Lesson Eight:
Fusion Reactors
H-Bomb - Tsar Bomb - the Biggest Bomb ever exploded:
Lesson Nine:
Effects of Radiation on the Human Body
http://www.nrc.gov/reading-rm/basic-ref/teachers/09.pdf
Units for conversion - Rems, Svs, Rads
http://www.jplabs.com/html/units_of_radiation.HTM
Note: That zero radiation is worth Nicks.
Absorbed Dose: http://en.wikipedia.org/wiki/Absorbed_dose
Equivalent Dose: http://en.wikipedia.org/wiki/Equivalent_dose
Lesson Ten:
Applications of Nuclear Technology:
Smoke Detectors
This type of detector is cheaper than the optical detector; however, it is sometimes rejected for environmental reasons and because it is more prone to false alarms than photoelectric smoke detectors. It can detect particles of smoke that are too small to be visible. It includes less than a milligram of radioactive americium 241 (241Am).[2] The radiation passes through an ionization chamber, an air-filled space between two electrodes, and permits a small, constant current between the electrodes. Any smoke that enters the chamber absorbs the alpha particles, which reduces the ionization and interrupts this current, setting off the alarm.
241Am, an alpha emitter, has a half-life of 432.2 years. This means that it does not have to be replaced during the useful life of the detector, and also makes it safer for people at home, as it is less radioactive. Alpha radiation, as opposed to beta and gamma, is used for two additional reasons: Alpha particles have high ionization, so sufficient air particles will be ionized for the current to exist, and they have low penetrative power, meaning they will be stopped by the plastic of the smoke detector and/or the air, reducing the risk of harm to people. (Source: Wikipedia)
Lesson Eleven:
Lesson Twelve:
Lesson Thirteen:
Half Life
Safety Considerations
1. http://www.osha.gov/SLTC/radiation/index.html
Powerpoints:
Practicals:
Decay using Excel -
Worksheets:
Answers to Complex Reasoning Questions for Chapter 28
http://seniorphysics.com/ch28_sol.html
Mistakes:
Chapter 28
Page 584. The scales on the graph are wrong.
On the y-axis, the 5 x 105 should be half way down next to the dotted line.
On the x-axis, the times should be 0, 15, 30, 45, 60 and the unit should be 'hours' not days.
Question 44. Answer in back of the 1997 edition of the book says Reaction II produces 9.61 x 1012 J/kg. This is wrong - the correct answer is 5.72 x 1014 J/kg) and Reaction II produces more energy per kg than Reaction I
Animations:
Nuclear Decay - The decay of 500 atoms of the fictional element Balonium
http://www.upscale.utoronto.ca/GeneralInterest/Harrison/Flash/Nuclear/Decay/NuclearDecay.html
Radioactive Decay - http://lectureonline.cl.msu.edu/~mmp/applist/decay/decay.htm
Chain Reactions - http://lectureonline.cl.msu.edu/~mmp/applist/chain/chain.htm
Nuclear Isotopes Half Iives - http://lectureonline.cl.msu.edu/~mmp/kap30/Nuclear/nuc.htm
http://seniorphysics.com/ncsp_1ed.html
school physics
http://www.schoolphysics.co.uk/age16-19/Nuclear%20physics/
http://www.lbl.gov/abc/Contents.html#experiment
http://www.nclark.net/NuclearChem
Updated by Nick Johnstone
5 October, 2008.